1. Field Of The Invention
The invention relates to diaphragm valves, particularly for containers for pressurized gas.
2. Prior Art
U.S. Pat. No. 2,388,988 (Mueser) teaches a valve combination which includes a flow passage having a seat and a diaphragm, having a central portion surrounded by an annular portion which is adapted to be flexed into and out of engagement with the seat to close and open the flow passage. The central portion of the diaphragm has a greater travel to the seat than the annular portion of a backing member engaging the central portion only of the diaphragm on the side remote from the seat. There is a manually operable stem rotatable to advance the backing member a distance commensurate with the travel of the central portion of the diaphragm in moving from open to closed position. An annular member surrounds the backing member and engages the annular portion of the diaphragm surrounding the central portion thereof. The backing member and the annular member each are movable with respect to the other. There is means responsive to the rotation of the stem to advance the annular member a distance commensurate with the lesser travel of the annular portion of the diaphragm.
U.S. Pat. No. 2,388,989 (Mueser) discloses a valve combination which includes a flow passage having a seat, and a diaphragm which is adapted to be flexed into and out of engagement with the seat to open and close the flow passage and of a diameter, relative to the diameter of the seat such that an annular portion of the diaphragm outside the bounds of the seat is free to flex. A main backing member engages the central portion only of the diaphragm on the side remote from the seat. An auxillary backing member is adapted to engage the annular portion of the diaphragm outside of the bounds of the seat. The main backing member and the auxillary backing member each are movable with respect to the other. There is a rotatable stem and differential screw means actuated thereby to move the main backing member a distance commensurate with the travel of the central portion of the diaphragm in moving from open to closed position and the auxiliary backing member a distance commensurate with the lesser travel of the annular portion of the diaphragm. The screw means has oppositely threaded sections of unequal pitch.
U.S. Pat. No. 2,679,378 (Uhlet er al.) teaches a high pressure control valve which includes a first body member having an inlet passageway. There is a raised valve seat around the inner end of the inlet passageway. The first body member has an enlarged chamber which surrounds the valve seat and which is defined by the edge of a shoulder portion. A flexible diaphragm is seated on the shoulder portion and extends across the valve seat for closing the same. A second body member is connected with the first body member outside of the region of the shoulder portion and is engaged with the diaphragm to hold the same sealed upon the shoulder portion. There is a valve actuator movable axially in the second body member for moving the diaphragm against the valve seat. The actuator has a diameter greater than that of the valve seat. The valve seat and the shoulder portion defines an annular groove. The first body member has an outlet passageway opening into the groove. A spring is located between the diaphragm and the floor of the groove for lifting the diaphragm from the seat. The spring is a unit structure comprised of continuous outer and inner rings held in spaced relation by spoke-like connecting webs with arcuate perforations between the webs. The outer ring is downwardly curved between the webs and the inner ring is upwardly curved between the webs. The crests of the curved portions of the outer ring are seated in the groove and guided by the shoulder portion. The inner periphery of the inner ring has a diameter greater than that of the valve seat and less than that of the actuator. Thereby, upon closing movement of the actuator, the pressure therefrom acts on the diaphragm for seating the same upon the valve seat. It also acts through the diaphragm upon the crests of the curved portions of the inner ring for compressing the same and the curved portions of the outer ring toward flat form and into the groove.
U.S. Pat. No. 2,767,956 (Rubin) teaches a diaphragm-type valve which includes a diaphragm for closing the valve against a seat in the valve by the action of a valve stem. The diaphragm is composed of a thermoplastic polymer of trifluorochloroethylene having an N.S.T. between about 250.degree. and about 350.degree. C. plasticized with between about 15 and about 35 weight percent of a lower molecular weight oil fraction of a polymer of trifluorochloroethylene boiling between about 230.degree. and about 400.degree. F. at 1 mm. of mercury.
U.S. Pat. No. 2,892,613 (Boteler) discloses a diaphragm-type valve which has a compressor with a socket therein and which has connecting means with one portion in the socket overlying the rim of an aperture in the bottom thereof and with another portion extending slidably through the aperture and adapted to engage a diaphragm. There is a slot in the one connecting means portion and a key carried loosely in the slot. The socket has an ellipse-like cross section at the one connecting means portion. The key measured in a cross-sectional plane at the connecting means portion is shorter than the major axis of the ellipse-like cross section and is longer than the minor axis of the ellipse-like cross section. At least the portion of the key which is located within the slot is supported by the compressor in spaced relation with respect to the bottom of the slot.
U.S. Pat. No. 3,157,383 (Price) teaches a diaphragm valve which includes a diaphragm clamped at its margin between a bonnet, and a flat diaphragm clamping surface of which makes a rounded junction with the internal wall thereof. There is a valve casing having a substantially straight bore of substantially constant cross-sectional area and a seating formed in part by the surface of a lateral opening which forms a rounded sweep of large radius joining it to a flat diaphragm clamping surface on the valve casing which extends inwardly at a substantial taper. The tapering sides of the opening run smoothly into the cross-section of the bore which thereby completes the seating. The diaphragm, when free, corresponds to the closed position of the valve, except at its margin, which slopes in the same direction but less steeply than the tapering part. The diaphragm in the closed position of the valve is pressed by an actuator to which it is attached, against the seating inward of the rounded sweep and is slightly stretched in the region of the rounded sweep. When the valve is opened, the diaphragm is retracted by the actuator and forms an outward corrugation into the bonnet within the clamped margin. The actual clamping surface on the bonnet over most of the periphery lies outside of the line at which the clamping surface on the casing joins the rounded sweep but over a narrow zone on each side extends inward so that in these zones a greater radial width of the diaphragm is firmly clamped. The inward extension is not great enough to interfere with the correct formation of the outward corrugation when the valve is opened.
U.S. Pat. No. 3,426,999 (Toinet) discloses a diaphragm valve which includes a body having an inlet opening and an outlet opening and a valve seat between the inlet and outlet openings, a cap and cooperating flanges, by which the cap is detachably secured to the body. A diaphragm is peripherally secured between the flanges. There is a valve actuator for moving the diaphragm selctively away from the seat to open the valve and toward and into engagement with the seat to close the valve. The flanges have complementary opposed surfaces between which the edges of the diaphragm are clamped. The surfaces are annular and coaxial and are defined by figures of revolution about their common axis. The axis is perpendicular to the direction of fluid flow through the inlet and outlet openings. The surfaces are inclined radially inwardly toward the valve seat so that the surfaces are inclined both to their common axis and to the direction of fluid flow through the inlet and outlet openings. The flanges have flat opposed surfaces perpendicular to the axis radially outwardly beyond said annular surfaces. The fluid passageways through the valve are circular adjacent the inlet and outlet openings and become progressively more oval adjacent the seat. The diaphragm is spherically concave in the open valve position. The valve body has interior surfaces that are convexly curved along the longitudinal midplane of the valve and that terminate along the midplane in sharp edges at the diaphragm. The convex curve of the valve body merges smoothly into the concave curve of the diaphragm in a substantially continuous surface along the midlplane thereby to avoid any abrupt break in the continuous surface. The portions of the continuous surface on opposite sides of the seat form a large obtuse angle with each other to reduce turbulence in the fluid flowing through the valve.
U.S. Pat. No. 3,802,462 (Trosch) teaches a remotely operable and manually operable membrane valve for fluid media which includes a housing and a membrane stretched across the housings. Inlet and outlet openings are located at one side of the membrane in the housing. A separating ridge separates the inlet and outlet openings. Deflection of the membrane toward the separating ridge controls the flow of the fluid medium through the valve. There are means admitting a control fluid to the other side of the membrane to control deflection thereof, and a pressure cap. An upstanding bolt is secured to the membrane. A hollow, transparent, threaded spindle surrounding the bolt is located at the other side of the membrane and engages the pressure cap. The spindle is threaded in the housing, is accessible from outside of the housing and effects movement of the pressure cap toward the membrane to control deflection of the membrane toward and away from the separating ridge and to permit visual inspection of the position of the bolt and hence of the membrane.
U.S. Pat. No. 4,014,514 (Priese et al.) discloses a valve which includes a valve body defining inlet and outlet ports and a closure port communicating therewith, a valve bonnet fixed on the valve body over the closure port and a compressor reciprocable toward and away from the closure port. A flexible diaphragm overlies the closure port and is movable by the compressor into engagement with the closure port to block fluid flow through the closure port and alternatively is movable away from the closure port to permit progressively greater fluid flow through the closure port. An annular limit plate is secured between the valve bonnet and the valve body. The plate includes a first non-compressive centering means for centering the limit plate relative to the valve bonnet, and a second non-compressive centering means for centering the limit plate relative to the valve body. There is a central passage means which permits at least partial passage of the compressor through the plate. There is also an upper surface positioned for abutting engagement of compressor stop means to halt motion of the compressor toward the closure port at a predetermined distance from the closure port so as to prevent excessive crushing of the diaphragm interposed between the closure port and the compressor. There is a lower surface having a first concavity adapted to abuttively support a bulbous diaphragm shoulder portion. The radially interior edge of the first concavity is substantially aligned with the should of the compressor when the compressor and diaphragm are fully retracted into a valve in a fully-opened position. The compressor and limit plate thus provide a substantially completely abuttive and supportive structure for the diaphragm when the compressor and diaphragm are fully retracted into a valve opened position.
U.S. Pat. No. 4,029,296 (Hartmann et al.) teaches a diaphragm valve arrangement which includes a pair of clamping members having respective juxtaposed surfaces which define with one another a gap and which bound an interior space. One of the surfaces has a projecting portion extending across the gap toward the other of the surfaces. A diaphragm of resilient material has an inner portion spanning the interior space and has a first region of uniform thickness and an outer portion adapted to be clamped in the gap. The outer portion has a marginal second region spaced exteriorly of and is of greater thickness than the first region. There is a recessed third region intermediate of and of lesser thickness than both of the first and second regions in unclamped condition so as to bound with the first and second regions a three-sided recess in which the projecting portion is lodged. The recessed region has relatively lesser material than the other regions due to the lesser thickness of the recessed region, to thereby substantially reduce the tendency of the material of the recessed region to flow toward the outer regions when in clamped condition.
U.S. Pat. No. 4,353,243 (Martin) teaches a fluid pressure controlled diaphragm actuated multiport valve which includes a first plate having a multiplicity of control fluid inlet means passing through the first plate. Each of the control fluid inlet means is connectable to a source of control fluid under pressure and is under independent pressure control. There is a second plate assembled adjacent the first plate having a multiplicity of fluid conduit means passing through the second plate. Each of the fluid conduit means opens opposite a corresponding control fluid inlet means in the first plate. The second plate further has a multiplicity of operatively interconnected, low dead volume fluid channel means on its inner surface peripherally surrounding each of the fluid conduit means. A flexible diaphragm means is disposed between the first plate and the second plate when the plates are assembled adjacent one another. The diaphragm means are so arranged and constructed as to seal any fluid conduit means to fluid flow when the corresponding control fluid inlet means is open to control fluid under pressure. The channel means are in independent operative fluid flow connection with each of the fluid conduit means when the diaphragm is not in sealing position with respect to the fluid conduit means and are not in operative fluid flow connection with each of the fluid conduit means when the diaphragm is in sealing position. The channel means are so arranged and constructed as to maintain operative fluid flow connection between any of the fluid conduit means which are not sealed. There is means for holding the first plate. The second plate and the diaphragm are in assembled adjacent relationship.
U.S. Pat. No. 4,376,523 (Goyen) teaches an assembly which includes a header pipe having an internal flow passage, a wall with a sealing surface, and an aperture through the sealing surface into the flow passage. An outlet pipe is mounted to and passes through the wall, crosses the flow passage and has a threaded end. There is a diaphragm-type valve having a body which includes a peripheral skirt adapted to bear against the sealing surface and a web. A threaded tubular member supported by the web is threadedly engaged to the end of the outlet pipe and is operative to bring the skirt toward and against the sealing surface, thereby to mount the diaphragm-type valve to the header pipe. The web provides a fluid passage extending between the flow passage and the outlet pipe. The diaphragm-type valves are disposed outside of the header pipe. There is a fluid controlling position between the end of the outlet pipe and the fluid passage. There is also port means for admitting control pressure to the diaphragm, a peripheral seal means is disposed in a sealing manner between the skirt and the sealing surface.